1. Field of the Invention
The present invention relates to a rotary self-advancing endoscope system including a rotating cylindrical body at least a part on the outer periphery side of an insertion portion, a program and a driving method for drive-controlling the rotary self-advancing endoscope system.
2. Description of the Related Art
Endoscopes are widely used in a field of medicine or the like to observe a parts such as an interior of a lumen, which is not directly viewable. Such an endoscope generally includes an elongated insertion portion and has been inserted into an examinee's body by manual operation of a user.
In recent years, there have been studied endoscopes (self-propelled endoscopes) configured to be inserted by self-propulsion. There are various types of such endoscopes. An example is an endoscope configured to be inserted into a large intestine via anus, wherein the endoscope is a rotary self-propelled endoscope which has a cylindrical rotating body including a helical portion and rotatable about an axis provided on an outer periphery side of an insertion portion and is configured to be capable of being automatically inserted into a body cavity by rotating the rotating cylindrical body.
In such a self-propelled endoscope, as an inserted length of an insertion portion into an examinee's body increases, a contact area of the insertion portion with the examinee's body increases, i.e., a frictional resistance-induced load on a drive source for driving a rotating cylindrical body increases. The load may increase rapidly, for example, if kinetic friction changes to static friction at the time.
Under such circumstances, there is proposed a technique for performing constant-speed driving by detecting a rotating state of a drive source such as a motor for driving a rotating cylindrical body and controlling a current applied to the motor such that the motor rotates at a constant rotation speed. This makes it possible to insert an insertion portion at a constant pace regardless of inserted length and prevent an increase in time required for insertion.
The present invention has as an object to provide a rotary self-advancing endoscope capable of being stably inserted without reducing propulsion, a program, and a method for driving the rotary self-advancing endoscope system.
The present invention has as another object to provide a rotary self-advancing endoscope capable of predicting and avoiding a stop of a drive source of a rotating cylindrical body caused by an increase in load and improving working efficiency, a program, and a method for driving the rotary self-advancing endoscope system.